package cn.bruce.java2;

import cn.bruce.java1.Person;
import org.junit.Test;

import java.lang.annotation.Annotation;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;

/**
 * 获取运行时类的方法结构
 *
 * @author bruce
 * @project_name JavaSenior
 * @package_name cn.bruce.java2
 * @create 2020-05-06 15:36
 */
public class MethodTest {
    @Test
    public void test1() {
        Class<Person> clazz = Person.class;
        //getMethods():获取当前运行时类及其所有父类中声明为public权限的方法
        Method[] methods = clazz.getMethods();
        for (Method m :
                methods) {
            System.out.println(m);
        }
        System.out.println("============");
        //getDeclaredMethods():获取当前运行时类中声明的所有方法。（不包含父类中声明的方法）
        Method[] declaredMethods = clazz.getDeclaredMethods();
        for (Method m :
                declaredMethods) {
            System.out.println(m);
        }
    }

    /*
    @Xxxx
    权限修饰符  返回值类型  方法名(参数类型1 形参名1,...) throws XxxException{}
     */
    @Test
    public void test2() throws ClassNotFoundException {
        Class<?> clazz = Class.forName("cn.bruce.java1.Person");
        Method[] declaredMethods = clazz.getDeclaredMethods();
        for (Method m :
                declaredMethods) {
            //1.获取方法声明的注解
            Annotation[] annos = m.getAnnotations();
            for (Annotation a :
                    annos) {
                System.out.println(a);
            }

            //2.权限修饰符
            System.out.print(Modifier.toString(m.getModifiers())+"\t");

            //3.返回值类型
            System.out.print(m.getReturnType().getName() + "\t");

            //4.方法名
            System.out.print(m.getName());
            System.out.print("(");

            //5.形参列表
            Class<?>[] parameterTypes = m.getParameterTypes();
            if (!(parameterTypes == null && parameterTypes.length == 0)) {
                for (int i = 0; i < parameterTypes.length; i++) {
                    if (i == parameterTypes.length - 1) {
                        System.out.print(parameterTypes[i].getName() + " args_" + i);
                        break;
                    }
                    System.out.print(parameterTypes[i].getName() + "args_" + i + ",");
                }
            }
            System.out.print(")");

            //6.抛出的异常
            Class<?>[] exceptionTypes = m.getExceptionTypes();
            if (exceptionTypes.length > 0){
                System.out.print("throws ");
                for (int i = 0; i < exceptionTypes.length; i++) {
                    if (i==exceptionTypes.length -1){
                        System.out.print(exceptionTypes[i].getName());
                        break;
                    }
                    System.out.print(exceptionTypes[i].getName()+",");
                }

                System.out.println();
            }


        }
    }
}
